ABSTRACT
Understanding the mechanisms that connect heat and electron transport with crystal structures and defect chemistry is fundamental to develop materials with thermoelectric properties. In this work, we synthesized a series of self-doped compounds Cu2+x Mn1-x GeS4 through Cu for Mn substitution. Using a combination of powder X-ray diffraction, high resolution transmission electron microscopy and precession-assisted electron diffraction tomography, we evidence that the materials are composed of interconnected enargite- and stannite-type structures, via the formation of nanodomains with a high density of coherent interfaces. By combining experiments with ab initio electron and phonon calculations, we discuss the structure-thermoelectric properties relationships and clarify the interesting crystal chemistry in this system. We demonstrate that excess Cu+ substituted for Mn2+ dopes holes into the top of the valence band, leading to a remarkable enhancement of the power factor and figure of merit ZT.
ABSTRACT
A sensitive and rapid LC-MS/MS method was developed and validated for the simultaneous quantitation of darolutamide and its active metabolite i.e. ORM-15341 in 50µL mice plasma using bicalutamide as an internal standard (I.S.) as per regulatory guidelines. Sample processing was accomplished through liquid-liquid extraction. Chromatographic separation was achieved using an Atlantis C18 column with an isocratic mobile phase comprising 0.2% formic acid:acetonitrile (35:65, v/v) at a flow rate of 0.8mL/min within 2.5min. Detection and quantitation were done by multiple reaction monitoring on a triple quadrupole mass spectrometer following the transitions: m/z 397â202, 395â202 and 429â255 for darolutamide, ORM-15341 and I.S, respectively in the negative ionization mode. The calibration curve was linear from 0.61-1097ng/mL for both darolutamide and ORM-15341. The intra- and inter-day precisions were in the range of 1.34-13.8 and 4.85-12.9 and 3.91-13.7 and 6.54-14.2%, for darolutamide and ORM-15341, respectively. Darolutamide and ORM-15341 were found to be stable under different stability conditions. The validated method was applied to a pharmacokinetic study in mice.
Subject(s)
Pyrazoles/blood , Animals , Calibration , Chromatography, Liquid , Liquid-Liquid Extraction , Mice , Reproducibility of Results , Spectrometry, Mass, Electrospray Ionization , Tandem Mass SpectrometryABSTRACT
Bornite Cu5FeS4-xSex (0 ≤ x ≤ 0.6) compounds have been synthesized, using mechanical alloying, combined with spark plasma sintering (SPS). High temperature in situ neutron powder diffraction data collected on pristine Cu5FeS4 from room temperature up to 673 K show that SPS enables the stabilization of the intermediate cubic (IC) semi-ordered form (Fm3[combining macron]m, aIC â¼ 10.98 Å) at the expense of the ordered orthorhombic form (Pbca, aO â¼ 10.95 Å, bO â¼ 21.86 Å, cO â¼ 10.95 Å) in the 300-475 K temperature range, whereas above 475 K the IC form coexists with the high temperature cubic (C) form (Fm3[combining macron]m, aC â¼ 5.50 Å). The ability of Se for S substitution to induce disorder and consequently to enhance the IC phase formation is also emphasized. This disordering effect is explained by the high quenching efficiency of the SPS method compared to conventional heating. The existence of topotactic phase transformations, as well as Se for S substitution is shown to have a significant effect on the transport properties. As expected, electrical transport properties indicate a change towards a more metallic behaviour with increasing Se content. The electrical resistivity reduces from â¼21.4 mΩ cm for the pristine Cu5FeS4 to â¼3.95 mΩ cm for Cu5FeS3.4Se0.6 at room temperature. A maximum power factor of 4.9 × 10-4 W m-1 K-2 is attained at 540 K for x = 0.4 composition. The influence of selenium substitution on the carrier effective mass and mobility is discussed based on single parabolic band approximation. Furthermore, a detailed investigation of the thermal conductivity by this isovalent anion substitution reveals a significant reduction of the lattice thermal conductivity due to the alloying effect. Finally, the important role of structural transitions in the thermoelectric properties is addressed. A maximum ZT of 0.5 is attained at 540 K for Cu5FeS3.8Se0.2 composition.
ABSTRACT
Lymphangioma are rare, benign, and hamartomatous tumors of the lymphatic vessels, that show a marked predilection for the head and neck region. Very few cases of Cavernous lymphangioma have been reported to occur in the lower lip. We report a rare case of Cavernous Lymphangioma of the lower lip in a 13 years old child who was treated surgically by excision and primary closure. Postoperative wound healing was satisfactory and there was no recurrence found till the last follow up.